Delta Air Lines Flight 191 was a regularly scheduled Delta Air Lines domestic service from Fort Lauderdale, Florida to Los Angeles, via Dallas that crashed on August 2, 1985, at 18:05 (UTC−05:00). The Lockheed L-1011 TriStar operating this flight encountered a microburst while on approach to land on runway 17L at Dallas/Fort Worth International Airport (DFW). The pilots were unable to successfully escape the weather event, and the aircraft impacted the ground over a mile short of the runway. The flight hit a car driving north of the airport and impacted two water tanks, disintegrating. The crash killed 136 of the 152 passengers and 11 crew on board, and the driver of the car. The National Transportation Safety Board (NTSB) determined that the crash resulted from the flight crew's decision to fly through a thunderstorm, the lack of procedures and training to avoid or escape microbursts, and the lack of hazard information on wind shear.

Contents

The Delta Air Lines Flight 191 aircraft was a Lockheed L-1011-385-1 TriStar (registration numberN726DA).[1] The aircraft was delivered to Delta on February 28, 1979, and had been operated continuously by the airline since that date.[2] The aircraft was powered by three Rolls-Royce RB211-22B engines. The day of the accident, Flight 191 was manned by three flight crewmen and eight cabin crewmembers. The flight was piloted by 57-year-old Edward N. Connors.[3] Connors had been employed by Delta Air Lines since 1954. He qualified to captain the TriStar in 1979 and had passed his proficiency checks. The NTSB report mentioned that other flight crew that had flown with Connors prior to the accident described him as a cautious pilot who strictly adhered to company policies.[4] The report also reported that Connors "deviated around thunderstorms even if other flights took more direct routes" and "willingly accepted suggestions from his flightcrew."[4] Since his qualification in 1979, Connors had passed all eight of the en route inspections he had undergone, and the NTSB report notes that he had received "favorable comments" regarding "cockpit discipline and standardization."[4] Connors had logged over 29,300 hours of flight time, 3,000 of which had been in the TriStar. The first officer on the day of the crash was 42-year-old Rudolph P. Price, Jr.[3] Delta captains who flew with Price described him as an "above average first officer" and possessing "excellent knowledge" of the TriStar.[4] Price had logged 6,500 flight hours, including 1,200 in the TriStar. The second officer on the accident flight was 43-year-old Nick N. Nassick.[a][5][3] He had logged 6,500 hours of flight time, including 4,500 in the TriStar.[3] Fellow Delta employees described him as "observant, alert, and professional."[4] The cabin crew consisted of flight attendants Frances Alford, Jenny Amatulli, Frieda Artz, Vickie Chavis, Diane Johnson, Virginia Lee, Joan Modzelewski, and Wendy Robinson.[3]

At 17:43:45, the Fort Worth ARTCC controller cleared the flight down to 10,000 feet (3,000 m).[6] The controller suggested they fly a heading of 250° toward the Blue Ridge approach. Captain Connors replied, "Well, I'm looking at ... a pretty good sized cell and I'd rather not go through it, I'd rather go around it one way or the other."[8] The controller tried to assuage Connors concerns, but the captain reiterated that he saw a storm cell in the vicinity of the suggested heading. The controller gave the flight a new heading.[6] At 17:46:50, the controller cleared the flight direct to Blue Ridge and instructed the flight crew to descend to 9,000 feet (2,700 m). The captain expressed his relief that the controller didn't send them on the original trajectory. At 17:51:19, the second officer commented, "Looks like it's raining over Fort Worth."[8] At 17:51:42, the Fort Worth ARTCC controller transferred the flight to DFW Airport Approach Control.[6] Approach control further cleared the flight to descend to 7,000 feet (2,100 m). Two minutes later, the controller asked the Delta flight to deviate by ten degrees and to slow their airspeed to 180 knots (210 mph). The flight acknowledged the request.[8] As the flight descended, the crew prepared the aircraft for landing. At 17:56:19, the feeder controller cleared the flight down to 5,000 feet (1,500 m). Nine seconds later, he announced, "There's a little rainshower just north of the airport and they’re starting to make ILS approaches ... tune up one oh nine one for one seven left"[8]

At 17:59:47, the Price said, "We're gonna get our airplane washed."[8] At around the same time, the captain switched to the arrival radar frequency and informed the approach controller that they were flying at 5,000 feet (1,500 m). The controller replied that the flight should expect to approach runway 17L. At 18:00:36, the approach controller asked an American Airlines flight that was two aircraft ahead of Flight 191 and on the same approach if they could see the airport.[6] The flight responded, "As soon as we break out of this rain shower we will."[8] At 18:00:51, Flight 191 was instructed to slow to 170 knots (200 mph) and to turn to heading 270°. Ahead of the flight was a Learjet 25 on the same approach.[6] Flight 191 was instructed to descend to 3,000 feet (910 m) at 18:01:34. One minute later, the controller turned the flight toward the runway and cleared them to fly the ILS approach at or above 2,300 feet (700 m).[6][8] Half a minute afterwards, the controller asked the flight to reduce their speed to 160 knots (180 mph) and the flight acknowledged. At 18:03:30 the controller advised, "And we're getting some variable winds out there due to a shower ... out there north end of DFW."[6] Several seconds later, one of the flight crew commented, "Stuff is moving in."[8]

At 18:03:46, the approach controller once again asked them to reduce their speed to 150 knots (170 mph) and handed the flight over to the tower controller. Twelve seconds later, the captain radioed the tower and said, "Tower[:] Delta one ninety one heavy, out here in the rain, feels good."[8] The tower controller replied that there was wind blowing at 5 knots (5.8 mph) with gusts up to 15 knots (17 mph). Connors acknowledged this. The flight crew lowered the landing gear and extended their flaps for landing. At 18:04:18, Price commented, "Lightning coming out of that one. ... Right ahead of us."[8] The captain called out that they were at 1,000 feet (300 m) at 18:05:05. Fourteen seconds later, he cautioned Price, "Watch your speed."[6] At the same time, the cockpit voice recorder (CVR) captured the beginning of a sound identified as rain hitting the cockpit. The captain warned Price, "You're gonna lose it all of a sudden, there it is." At 18:05:26, the captain told Price, "Push it up, push it way up." Several second later, the CVR recorded the sound of the engines spooling up. Connors then said, "That's it." At 18:05:36, Connors exclaimed, "Hang on to the son of a bitch."[b][6][9] From this point, the aircraft began a descent from which it never recovered. The angle of attack (AOA) was over 30° and began to vary wildly over the next few seconds.[10] The pitch angle began to sink and the aircraft started descending below the glideslope.[11]

At 18:05:39, Price asked, "What's the VRef?"[8] Five seconds later, the ground proximity warning system (GPWS) began a series of "whoop whoop pull up" audible warnings. One second after the warnings began, the captain declared, "TOGA."[8] The aircraft continued to sink with the AOA varying by over twenty degrees. When the warnings began, the aircraft pitched upward but did not cease its descent. By the time the captain called "TOGA," the aircraft was descending over 50 feet (15 m) per second.[10]. In the seconds before the initial impact with the ground, the rate of descent slowed to approximately 10 feet (3.0 m) per second.[12] At 18:05:52, the aircraft hit a plowed field 6,336 feet (1,931 m) north of the runway and 360 feet (110 m) east of the runway centerline on a heading of 167°.[13] This initial impact was not forceful enough to compromise the airframe, and the flight continued traveling at ground level.[12][13] The main landing gear left shallow depressions in the field that extended for 240 feet (73 m) before disappearing and reappearing a couple times as the aircraft approached Texas State Highway 114.[13]

The aircraft impacted a highway street light and its nose gear touched down on the westbound lane. At the time, there was a traffic jam on the highway. The aircraft's left engine hit a Toyotacoupe driven by 28-year-old William Mayberry, killing him.[7][13] As the aircraft continued south, it hit two more street lights on the eastbound side of the highway and began fragmenting. The left horizontal stabilizer as well as some engine pieces, portions of the wing control surfaces, and parts of the nose gear came off the aircraft as it continued traveling along the ground. Some witnesses later testified that there was fire emerging from the left wing root.[6] Surviving passengers reported that fire began entering the cabin through the left wall prior to the final impact.[14] The aircraft grazed one water tank about 1,700 feet (520 m) south of the highway and impacted a second water tank just beyond the first. As the left wing and nose struck the water tank, the fuselage rotated counterclockwise and was engulfed in a fireball.[6] The fuselage of the aircraft from the nose rearward to row 34 was destroyed.[14] The tail of the aircraft emerged from the fireball, skidding backwards, and coming to rest on its left side before being rotated upright by the wind gusts.[6]

All airport fire and emergency units were alerted within one minute of the crash. 45 seconds after first being alerted, three airport fire trucks from the airport's fire station No. 3 arrived at the scene of the crash and began fighting the post-accident fire. Additional units from fire stations No. 1 and No. 3 arrived within 5 minutes, and despite high wind gusts and heavy rain, the fire was mostly under control within 10 minutes after the alert was sounded.[15]

The first paramedics arrived at the scene within 5 minutes of the crash, and triage stations were immediately established. In later testimony to NTSB officials, on-site EMTs estimated that without the on-scene triage procedures, at least half of the passengers who survived the crash would have died.[15] Most of the survivors of Flight 191 were located in the rear smoking section of the aircraft, which broke free from the main fuselage before the aircraft hit the water tanks. Authorities transported most of the survivors to Parkland Memorial Hospital.[16]

Two of the passengers who initially survived the impact died more than thirty days after the accident. On the ground, an employee of an airline who assisted in rescuing survivors was hospitalized overnight for chest and arm pains.[15]

The cockpit and passenger section forward of seat row 34 had been completely fragmented by impact with the water tanks and post-crash fires; all but eight of the occupants in this section were killed. The remainder of the surviving passengers and crew were in the rear cabin and tail section, which separated relatively intact and landed on its side in an open field. Overall, the disintegration of the Tristar was so extensive as to render the NTSB investigation quite difficult. Survivors reported that fire broke out in the cabin prior to hitting the tanks, and had begun spreading through the aircraft's interior, which is consistent with the right wing's collision with the light pole and fuel tank ignition. Some of the people in the tail section were unable to free themselves due to impact injuries and had to be extricated by rescue crews. Most survivors were also soaked with jet fuel, further adding to the difficulty of exiting the wreckage.

Delta Air Lines Flight 191 has the second-highest death toll of any aviation accident involving a Lockheed L-1011 anywhere in the world after Saudia Flight 163.

Numerous public safety agencies responded to the crash, including the Dallas/Fort Worth Airport Department of Public Safety, the Texas Department of Public Safety, the Irving Fire Department, the Irving Police Department and all available third watch personnel from the Dallas Police Department's Northwest Patrol Division and the Northeastern Sector of the Fort Worth Police Department's Patrol Division.

After a long investigation, the National Transportation Safety Board deemed the cause of the crash to be attributable to pilot error (for decision to fly through a thunderstorm), combined with extreme weather phenomena associated with microburst-induced wind shear.[15]

The NTSB attributed the accident to lack of the ability to detect microbursts aboard aircraft – the radar equipment aboard aircraft at the time was unable to detect wind changes, only thunderstorms. After the investigation, NASA researchers at Langley Research Center modified a Boeing 737-200 as a testbed for an on-board Dopplerweather radar. The resultant airborne wind shear detection and alert system was installed on many commercial airliners in the United States after the FAA mandated that all commercial aircraft must have on-board windshear detection systems.

The NTSB was also critical of the airport for failing to notify emergency services in surrounding municipalities in a timely manner. While the airport's on-site emergency services were notified almost immediately, the DFW Department of Public Safety (DPS) Communications Center did not begin notifying off-site emergency services until nearly 10 minutes after the crash, and did not finish its notifications until 45 minutes after the crash. During notifications, DPS also failed to request ambulances from the adjacent communities of Irving, Grapevine, and Hurst; however, Hurst responded with ambulances after personnel at its ambulance company overheard the airport crash report on a radio-frequency scanner. The NTSB concluded that the overall emergency response was effective due to the rapid response of on-airport personnel, but found "several problem areas" which under different circumstances "could affect adversely the medical treatment and survival of accident victims at the airport".[15]

Following the crash and the ensuing NTSB report, DFW's DPS made improvements to its post-crash notification system, including the introduction of an automated voice notification system to reduce notification times. In 1988, following the crash of Delta Air Lines Flight 1141 while taking off from DFW, DPS completed its notification of nearby emergency services in 21 minutes; the NTSB described this as a "significant improvement" over response times after the Delta Flight 191 crash. Based on the improved response times, the NTSB issued a Safety Recommendation on January 9, 1990 calling for airport executives nationwide to consider the benefits of using automated voice notification systems for their emergency aid notifications.[17]

The crash of Delta Flight 191 resulted in the longest aviation trial in American history, lasting fourteen months during 1988 to 1989 and presided over by the Hon. David O. Belew. In re Air Crash at Dallas/Fort Worth Airport on Aug. 2, 1985, 720 F. Supp. 1258 (N.D. Tex. 1989) aff'd sub nom. In re Air Crash at Dallas/Fort Worth Airport on August 2, 1985, 919 F.2d 1079 (5th Cir. 1991), cert. denied, sub nom. Connors v. United States, 502 U.S. 899 (1991). The trial featured the first use of computer graphic animation as substantive evidence in federal court, which is now routine, and became the American Bar Association Journal cover story “The Final Minutes of Delta 191,” ABA Journal (Dec. 1989).